1. WASTEWATER TREATMENT Lecture notes for 22nd of September Dr. Pál Mihátz (Fac. of Chem. Eng.) Dr. István Licskó and Anita Szabó (Dep. of Sanitary and Environ. Eng., Fac. of Civil Eng.

2. Earth is very rich in water: >70% of the planet`s surface More than 97 % of this is salt water 30 % of the world`s renewable fresh water supplies are already being used Enough fresh water is available to support over 20 billion people, if it was evenly distributed. Because of variable climatic and geologic condition it is available to 6 billion people.WATER

3. Salt water in oceans and seas 97,4% Groundwater 0,59% Ice caps and glaciers 1,98% Lakes 0,007% Soil moisture 0,005% Atmosphere, rivers, plants, animals 0,001% Fresh water 2,6% 0,014% WATER RESOURCES

4. THE HYDROLOGIC WATER CYCLE infiltration Groundwater flow

5. SOCIAL WATER CYCLE Diversion, abstraction Water use (domestic, communal, industrial, agricultural) Effluent drainage (return to natural recipient) On-site (non-diversion) water uses (transportation, recreation)

6. WATER SOURCES Subsurface waters:  ground water  water of deep confined aquifers  karstic water  bank filtered water Surface waters:  river  lake  reservoir

7. WATER USES drinking water irrigation industrial fish ponds recreation shipping nature reserve

8. Other aspect: 1. Domestic - water for drinking, cooking, personal hygiene, lawn sprinkling, etc. 2. Public - water for fire protection and street cleaning and water used in schools or other public buildings 3. Commercial and Industrial - water used by restaurants, laundries, manufacturing operations, etc. 4. Loss - due to leaks in mains and house plumbing fixtures

9. WATER DEMAND human’s need (2-4 l/day) agriculture (41% of the water) cool power generators (38%) industrial manufacturing (11%) USA (1993)

10. WATER 30% of the world’s people have inadequate sanitation Consequence: cholera, typhoid, hepatitis, etc. 25 million deaths annually are caused by water pollution (mostly infants) Damage to aquatic ecosystem

11. POLLUTANTS IN WASTEWATER different size –dissolved <0.01  m –colloidal 0.01-1.0  m –suspended 1.0-100  m –settleable suspended solids >100  m inorganic –mainly dissolved –conventional components salt content sulphate –inorganic micropollutants Heavy metals (Hg, Cd, Pb, Cr, Ni, Cu, Zn, Ag, etc.) As, CN -, Sb

12. THE ROLE OF CONCENTRATION All components can be –Toxic matter –Stimulating matter (trace elements) depending on concentration (Pick salami can also be toxic!!! (if you eat that much))

13. WHAT IS WATER POLLUTION? Along its path through the hydrologic cycle, the water is polluted by natural (animal, plant) and anthropogenic factors Type of pollutants in a certain catchment depends on: –Geochemistry –Meteorology –Topography –Ecology Type of pollution entrained along the social water cycle depends on the type and technological level of the particular human activities

14. WHAT IS WATER POLLUTION? In a particular catchment, at a particular point and at a particular time the level of the pollution is the result of the interactions of the natural and social water cycles Definition (Klein, 1972, Felföldy, 1974) Water pollution is understood to include all impacts, as a result of which the quality of water is changed in a manner to make it less suited, or completely unsuited to human use and to sustain natural biological processes occurring in it.

15. WATER QUALITY MANAGEMENT Water quality = sum of different properties of water Classification of water water use = certain objective to reach parameters (physical, chemical, biological, bacteriological) C B D A wastewater Industry Recreation wastewater Environmental protection

16. DEFINITIONS EMISSION (E) = input load = the amount of pollutant discharged in a unit of time [M/T] C B D A wastewater Industry wastewater E (kg/d) I (kg/m 3 ) E (kg/d)

17. DEFINITIONS IMISSION (I) = pollutant concentration developed as the effect of pollutant load = effect of emission [M/L 3 ] C B D A wastewater Industry wastewater E (kg/d) I (kg/m 3 ) E (kg/d)

18. WATER POLLUTION CONTROL The level of water pollution can be controlled by engineering measures implemented along the natural and social cycles. Interference with the natural cycle has triggered recently violent oppositions in some groups of society and political parties (green movements), as a consequence of which the only viable alternative of pollution control will comprise engineering, economic and legal measures along the social water cycle in the foreseeable future already. Definition the required component concentrations at the selected river section

19. WATER QUALITY MANAGEMENT if water quality is not good enough  action is needed »science »technology »economy + legislation

20. defence prevention activity pollutant load water quality ecosystem monitoring water use strategies + alternative proposals classification trends causes and consequences decision -technology -economy -legislation requirements (limiting values /standards) intervention modelling

21. TOOLS OF WATER POLLUTION CONTROL Engineering measures Legal measures institutional

22. ENGINEERING MEASURES AGAINST POLLUTION end of pipe solutions (decreasing load at the end of the technology = WASTEWATER TREATMENT) changing the technology (increasing effectivity) changing inputs (other types of raw materials) changing the product increasing re-use changing the location of discharge point (receiving water body) changing the capacity of environment (reservoirs) changing the time of discharge (storage of polluted water) dilution other methods (aeration, etc.)

23. LEGAL MEASURES Water Act, Environmental Act Effluent quality standards Fines Economic aspects

24. INSTITUTIONAL Monitoring Evaluation Declarations

25. Wastewater used water originated from human activity (including metabolism) contains pollutants WASTEWATER Pollutants The matters entering to the recipient that change the existing biological, biochemical processes significantly; and deteriorate or prohibit the further water use

26. Wastewater treatment Decreasing the pollutant concentration of wastewaters before entering into the recipient WASTEWATER TREATMENT Possible recipients Surface water Subsurface water Soil

27. DOMESTIC WASTEWATER (sewage) human wastes and washwater from homes INSTITUTIONAL WASTEWATER (sewage) human wastes and washwater from public buildings, commercial establishments MUNICIPAL SEWAGE mixture of sewage and industrial wastewater INDUSTRIAL SEWAGE used water from manufacturing processes - contains different chemical compounds AGRICULTURAL WASTEWATER (e.g. liquid manure) STORMWATER surface runoff caused by rainfall - carries organics, suspended and dissolved solids, etc. TYPES OF WASTEWATERS

28. domestic and institutional wastewaters (sewage) Volume depends on the use of drinking water. The volume of the drinking water use depends on technical and cultural level of population, country, region, settlement. Industrialised countries: 100-160 liter/person/d Developing countries: <<100 liter/person/d Hungary: 90-100 liter/person/d (Budapest: 180 liter/person/d) industrial wastewaters Volume depends on the type of industry, number of factories, workshops, the level of applied technology, etc. Cooling water, wastewaters from metallurgy, chemical industry, food industry, etc. WASTEWATER VOLUMES

29. agricultural wastewaters Liquid manure (pig farms, cow farms, poultry farms) Volume depends on the types of the farm, number of animals, technology level, educational level of employees, etc municipal wastewaters Sewage water + industrial wastewater + infiltration (exfiltration) Infiltration: 5-40% Exfiltration: 5-15% WASTEWATER VOLUMES

30. COMPOSITION & VOLUME OF MUNICIPAL WASTEWATERS VERY HIGH VARIATION –TYPE OF COMMUNITY RESIDENTAL AREA RECREATIONAL AREA OFFICES –TYPE OF INDUSTRIES –AMOUNT OF SURFACE WATER (TYPE OF COLLECTION SYSTEM) –DIFFERENT HABITS EATING TYPE OF DETERGENTS

31. YEARLY VARIATION

32. VARIATION WITHIN A YEAR

33. VARIATION WITHIN A DAY 721 Time [h] Consumption or hydraulic load [m3/h]

34. Hungary UTILITY GAP 50%